City Manager Rod Swope said he is prepared to keep the fluoride out until city officials can determine whether the compound commonly used to prevent tooth decay is causing the leaching of copper in residential pipes. Public Works has been out of compliance with U.S. Environmental Protection Agency copper standards for the Mendenhall Wastewater Treatment Plant.

"I think folks are going to have to hang in there with us for a few months longer until we figure out what's going on here," Swope said.

If fluoride is found to be the problem, he suggested the city may not restore it to drinking water. That move would give the public a choice, he said, adding that fluoride benefits are a source of debate among medical providers nationally.

Public Works turned off the fluoride June 26, 2003, after reviewing research, Director Joe Buck said. Buck wants to keep the fluoride off until July to study the effects of copper levels without fluoride in the drinking water, he said.

But area doctors and dentists want the fluoride back on, saying patients - especially children - are being deprived of fluoride's benefits.

"Our main position is we just want to see fluoride get back in the water," said dentist Kristen Schultz, president of the Juneau Dental Society. "It's just going to be better off for everyone's dental health."

Schultz plans to send a letter to Mayor Bruce Botelho and the Juneau Assembly later this week, asking that fluoride be put back in drinking water.

Meanwhile, doctors and dentists are encouraging patients to take fluoride supplements daily. This will mean added costs for parents, because fluoride supplements are available only through prescription, Schultz said.

In response, Fred Meyer is ordering additional quantities of fluoride supplements, and has put generic tablets on sale for $1.99 per 100 tablets for 1 and 0.5 milligram sizes, said Rob Boley, a spokesman for the retail chain based in Portland, Ore.

Pediatrician Dr. Amy Dressel sent out a general letter on Friday telling medical providers to administer fluoride supplements with suggested dosage amounts.

Dressel tells breast-feeding mothers to drink city water so they can get fluoride to their babies, she said. She administers fluoride supplements to children who live at houses with well water. Also, only two dental providers accept Denali KidCare - a form of Medicaid insurance for dental care, Dressel said. If Juneau sees increased amounts of dental decay, the two providers may not be able to handle the increased loads, she said.

"It's a huge issue because kids need fluoride in their teeth to grow," Dressel said.

The issue started after the Public Works Department was trying to find ways to reduce copper levels in the treated wastewater. Copper levels have not exceeded water quality standards, but have been out of compliance with the EPA permit at the wastewater plant, Utilities Superintendent Scott Jeffers said.

Officials were researching ways to lower those levels and found data that shows fluoride impacts lead pipe systems, Buck said. Public Works has not found any data showing the impacts of fluoride on copper, he said. That is why the department wants to conduct a one-year test of whether fluoride causes the copper in residents' pipes to leach.

"It's a significant enough issue that (the state Department of Environmental Conservation) and EPA have put limits on how much copper can go into the Mendenhall River," Buck said.

The strict copper standards, set by DEC, are because of the damaging effects copper has on freshwater aquatic life in the Mendenhall River and the Mendenhall Wetlands State Game Refuge, Buck said.

Copper can kill aquatic life, stunt its growth and cause decreased fertility, said Rebecca Smith, an environmental specialist at DEC. Copper can bond to the gills of fish, and cause problems with in chemical balance, she said.

The copper limit in the EPA permit was set at 8.36 parts per billion, Jeffers said. Since the city turned off fluoride, copper concentrations in the treatment plant's effluent have dropped from an average of 16.7 parts per billion in fiscal year 2003 to 13.9 parts per billion so far for fiscal year 2004, he said.

Besides shutting off the fluoride, the city is trying to get EPA to change the copper standards outlined in the permit, Buck said.

If EPA disagrees, Jeffers said the city is prepared to investigate other water treatment options.

Water fluoridation provides a more frequent exposure of fluoride to the teeth than topically applied gels, said Brad Whistler, dental officer with the state Department of Health and Social Services. It costs about 98 cents per person for a community the size of Juneau, he said.

Community water fluoridation was recognized by the U.S. Centers for Disease Control and Prevention as one of the top 10 public health accomplishments of the last century, Whistler said.

Studies have shown a reduction in tooth decay due to water fluoridation to be as much as 60 percent in baby teeth and 35 percent in permanent teeth, Whistler said.

Fluoride makes the tooth enamel more resistant to acid production and promotes repair of enamel after exposure to acids, Whistler said.

Buck said he was not required to notify the medical community but said, in retrospect, that he should have. Eventually a medical provider noticed that the fluoride levels were low.

On Friday, Buck sent a letter to health care professionals notifying them the fluoride had been turned off. He said the drop in copper levels so far would not be enough to recommend the removal of fluoride from the system and it may be restored July 1.